Once In a Blue Moon
by Seedy Bea
Summary: What do werewolves do at a blue moon?


Prologue

**Prologue**

What you probably know is that every lunar month, there is a full moon.

What you probably know is that every full moon, werewolves appear, viciously clawing their way out of their human forms.

What you probably don't know is that on some rare lunar _years_ at a random point in time, the moon – influenced by the alignment of the sun, the planets, and our nearer solar neighbours – will tilt slightly off its axis just enough to bring about that rarest of occasions: a blue moon.

When most people hear the words "blue moon," they think of pixies, fairies, and romance. And while all these things are common to blue moons, the most significant event of the blue moon has to do with werewolves.

There was a blue moon in April 1978. It happened just a week after the full, and three days after my story begins.

**Chapter One**

James Potter raced down one of the many, seemingly endless corridors in Hogwarts, his arms full of food. He swung around a corner, pounded past a group of startled first-years, ripped through a tapestry, jumped down the flight of stairs concealed behind it, and flew out the bottom, straight into a warm thing that squealed.

"Oomph," he grunted as he hit the floor. How embarrassing.

Mind you, that had sounded like a girl, so as an impressive way to get up, he whipped out his wand, he pointed it at himself, and shouted "_Volo_!" He rose off the ground about three feet until "_Finite incantatem_!" and dropped lightly to the floor.

He turned to see who he'd run into, and almost wished he hadn't.

Lily Evans was looking at him quizzically from the floor.

"Made that charm up yourself, did you?" she asked, getting to her feet and straightening her hair.

"No, Remus has to take the credit for inventing that one, and in our first term, no less. He said he'd been studying Latin at his Muggle school. He also mentioned he was better at it than everyone else. I guess it just goes to show he's not above boasting, doesn't it?"

He cringed. He'd been chattering; sounding dorky. Remus hadn't even said that, he'd said he was good, not the best. Not being able to talk to her was just one of the reasons she hadn't noticed him properly yet. Except for that incident in their fifth year… but he didn't like to think about that.

But she wasn't looking like she was trying not to laugh in his face, just thoughtful.

"Interesting… it means 'I fly', right? No need for a broomstick anymore…well, except for speed, of course."

"Speaking of broomsticks, did you see the match on Saturday? We won, three-hundred and ninety to twenty."

"I know. I _was _there. And don't start telling me how you personally scored twelve of those goals and set up all the rest. You didn't do _all _of it. It was only five goals and three set-ups."

He tried to look shocked, but he failed. "How did you know that's what I've been saying? And I've never seen you at a Quidditch match!"

"I _do_ watch, you know," she said tartly. "And I _do_ support Gryffindor. I mean, just because one player is a numbskull doesn't mean all of them are…and I overheard you telling Rosie about your Quidditch triumphs. And Harriet, and Mandy, and Hillary, and…"

"Okay, okay, I'll shut up about it."

He grinned, wishing he could have done better than that_._

Without thinking, they'd been walking as they talked, and they had now arrived at his original destination: the hospital wing.

"Do you want to come in with me? I'm going in to see Remus; he's had a tussle with the Whooping Willow."

"The Whomping Willow? Ooh, that sounds serious, and Madam Pomfrey only lets best friends in for serious cases. That's why you were coming from the kitchens with your arms full of food, I suppose? Did you notice you'd dropped it?" She grinned mischievously at him.

"That? Easy," he said, summoning his stack of food , using the _Accio_ charm. "You can carry half and come in with me, seeing you were kind enough to point out that I'd lost it."

"Blast, now I've got an excuse to go in. Can't though, I've got Transfiguration. And I don't want to be on McGonagall's bad side."

"Ah well. But Lily, you know how there's a Hogsmeade visit this weekend? Well I was just wondering…maybe we could…go together?" _Did that sound bad? I think that sounded bad…_

"Now why would I want to do that?" she teased. _Oh heck, it sounded bad all right!_

"Ahhhh…well, I thought we could go to The Three Broomsticks. I'd pay," he added hastily, wishing he'd gone into the hospital wing when he had the chance.

"Now, Potter, I've been turning you down for seven years, why would I break a long-standing tradition like that?

"I don't know, but would you?" James muttered.

"Well… I might just think about it. If I don't get a better offer, that is. Bye!" she said heading off to her class.

Now James was feeling stupid. Why had he just asked her out like that? Oh well, he'd go in and ask Remus what he'd done wrong.

"Moony! Hungry?"

Remus' head snapped around. "Oh, hi Prongs. Why are you acting like that?"

"Acting like what?" asked a bemused James

"Too perky. You just came from History of Magic. You should be almost asleep. Why are you so perky?"

"Hmm…possibly something you'll never know, possibly something you will know."

"So…are you going to tell me?"

"Obviously." James related what had happened outside. When he got to the part where he had asked Lily out, Remus snorted half the glass of pumpkin juice Madam Pomfrey had left.

"You did _what_?"

"I asked her to come with me to Hogsmeade."

"Prongs, _Prongs_, _**Prongs**_, _**PRONGS!**_Bumbling around might be cute in the eyes of some girls, but I don't think Lily Evans is one of them. She won't go for cute; she'll go for smart, sensitive and slightly romantic. Just remember the three Ss and it just might work."

"Great, good advice, but what I need you to tell me is if she's actually going to go to Hogsmeade with me!"

"Of course she is. She was fooling with you. Tonight in the common room, walk up to her, and ask again. Look serious. These are the words you have to say: 'So you're going with me to Hogsmeade?' She says 'yes,' you plan where you meet up beforehand. Nothing to it."

If only.

Mud. It was all over the place. Most of it was on the Gryffindor Quidditch team.

James still hadn't approached Lily. He'd been too embarrassed. When he arrived in the common room, after talking to Remus about a lot of other unrelated things, she'd been sitting with friends, doing homework. He could have gone over to sit with her, but that would mean sitting with all her friends as well. And they'd giggle. And James hated sitting with giggly girls. So he'd gone over to the other side of the room, to sit with Sirius and Peter, to pretend to do his own homework and wait for an opportunity.

It never came; they all finished their homework at the same time. Then they went up to the dormitory. He considered waiting until everyone was gone, and then summoning Lily from her dormitory. But he figured that would be idiocy. She'd be asleep, or if not, she'd be talking to her friends, and they'd be very surprised to see her fly out the door. Not good.

Every time he'd seen her the next day, other girls had surrounded her. This pattern continued for the rest of the week, leaving him now, on Friday night, desperate. Quidditch practice was only just over, and he was trying as hard as he could to figure out a smart, sweet and slightly romantic way to talk to her.

Remus walked out of his dormitory, going down to the common room, planning to do his Arithmancy homework. Halfway down the stairs, he came across James, who was repeatedly banging his head on the wall, muttering, "Think. Think. Think."

"Think about what?"

"Some triple-s way to talk to her."

"You mean you haven't even spoken to her yet?"

"How do you get that? Well… no."

"Oh for… come with me. Do your homework, while we wait for your opportunity."

Lily was doing her homework, setting an example to the younger kids. As a prefect, she had to. She saw James come out of the boy's dormitory with Remus. They set up their homework on an adjacent table next to Sirius and Peter, but they didn't actually seem to be doing much work; rather, they were looking more at her than their homework, and they kept whispering to each other.

She stifled a giggle. Remus was giving James girl advice. She was sure of it. This could be fun.

**Chapter Two**

"Okay, she's smiling, which means she's in a good mood, or she's figured out something extremely mischievous."

"Mischievous? Lily doesn't do mischievous."

Remus was telling James his deductions about everything Lily did, and he was trying to poke a hole in each one.

"Not so you'd notice she doesn't. She's better at covering up than we are. Remember that time the Hufflepuff team's brooms started flying in formation in the entrance hall?"

"That was us."

"Well, yeah. But she said afterwards that she wished she'd thought of it."

"Okay, so she's either in a good mood for some reason, or she's cracked something mischievous, which is why she's happy. Which one is more likely?"

"Probably not mischief, unless she's had some sudden inspiration. But as she's happy, you can go over there, and be accepted better. So why don't you?"

"Because it's Lily. It's not Darlene, or Esme, or Bella, or any of the other girls. I can smooth-talk them, because I don't really – _like_ them like them. This is a girl I've had a crush on since I first saw her. When I try smooth-talking, it comes out wrong. Okay?"

"Go over there and talk to her, you idiot. She likes you. I think."

"You think. Great. I'm filled with confidence that –"

"Shut up and go over there. I don't know why you're arguing, you just said that you really liked this girl."

"Which is why I can't do this," grumbled James, getting up all the same.

As he walked over, he felt like the world slowed down, giving him time to go over all the things that could possibly go wrong. The eight second walk took about eight centuries. He felt like the whole common room was staring at him, and he blushed. _Looking around is a mistake. No one's looking at you. And do something about that blush! _He lectured himself.

When the ordeal of the walk was over, he found himself at the desk, standing dorkily over it, with Lily looking at him quizzically.

"… Hi." He said, and then mentally bashed himself in the head. _Great starting line, Potter_.

"Hi," replied Lily. _She spoke to him! Hallelujah!_

"Can I sit here?" he asked. Lily smiled that smile again. _He loved that smile._

"Sure." _He was going to sit next to her! Lady Luck loved him!_

He sat down. "So we're going to Hogsmeade tomorrow, then?" _get it over with_

"What gave you that idea?" _Oh help… better try something quick!_

"Well, you said you were going to, and I still want to, so I don't see any reason for us to not be going." This was good. That had been smart and fast. Best of all, it hadn't sounded like something a dork would have said. He was coming back.

"Actually, what I said was, 'If I don't have a better offer.' I think Severus' offer counts as better than yours."

"Severus'… but he's a… he called you a…" He stopped. It would only get worse. What a fall. From smart and fast to stammering and gasping. Even a dork would do better than that.

"Called me what? I don't recall him saying anything nasty to me. Well, I've finished my homework; I'd better get to bed. Gotta be fresh for my date."

She left him gaping.

"This looks bad." Said Remus as James got back to their table.

"It's bad. She's going to Hogsmeade with Snivellus. _Snivellus!"_

"Wha-ha-ha-ha-ha… you're kidding me."

"I'm not. Her exact words were 'I think Severus' offer counts as better than yours.'"

"Ohhhh. That smile was mischief. Directed at you. And I must admit, you looked funny."

"What? No, don't repeat yourself, I heard you. So she's having a laugh at my expense. I can take that. But how am I going to tell her I know that before she goes to sleep?"

"This is insanity, James. Let's forget it, and you can talk to her in the morning."

"I might miss her, and she might think I didn't think about it, took her word for it, and went on my own. Besides, we're here now, so why not?"

'Here' was the bottom of the corner of Hogwarts that ended in the girls' dormitory tower. James had come up with a plan to get to Lily. He would fly up to her dormitory window under his invisibility cloak, watch, and wait. He knew for a fact that most nights she stayed up reading. If she showed any signs of going to bed before the other girls, he'd cast a wakefulness charm on her. It didn't stop her being tired; it just stopped her going to sleep. Then when she was the only one awake, he'd take off the cloak. They'd talk. He just hoped that this wasn't too romantic.

"Okay, I'm ready. You're going to wait down here, right?"

"All night, if you transfigure a couple of these rocks into blankets and a bed. Mosquito net would be nice, too. And a bedside table. A fireplace wouldn't go down too badly, either."

"I'll take that as a yes. Transfigure your own bedroom."

Remus sighed. "If I can't stop you going, at least put these on."

"What are they?"

Remus sighed again. "Censoring glasses. They'll do the same as your normal ones, and also censor out anything deemed inappropriate to the wearer. You do realize that girls get changed in their bedrooms?"

"Heck. Okay, give 'em here."

He donned the glasses and cloak, and then obviously kicked off, because there was a soft whooshing sound that moved off quickly. Remus was left sitting on a cold rock. He'd never been much good at transfiguration.

James soared up the side of the tower, feeling good. He only felt this alive when he was flying. As he neared the top, he slowed a bit, looking in through the windows. Lily's was near the top. Good! She was still awake, reading. A couple of other girls were up as well, chattering and giggling away in a corner. He watched them for a while. That was the thing about invisibility cloaks: you could perv without anyone knowing. But not with these glasses, he realized, as they blacked out. And Remus had put a sticking charm on them. _That crafty fox! Not that I would, _he added quickly._ Of course not._ Remus thought of everything. The lenses went opaque again, and the three chatting girls were climbing into bed, still talking. He looked over at Lily again. She was putting her book down, obviously preparing to go to bed as well. Not in the plan. He charmed her. She picked up her book again. The girls had stopped talking. About thirty minutes and five charms later, she was the only one left awake. And she looked very tired. Probably liable to be cranky. Well, he had to give it a go. He dipped under the window, pulled off the cloak, set it hovering in midair, and rose up again. She noticed him immediately. Dropping her book, she ran to the window, and opened it, only to hiss angrily, "What in hell do you think you're doing, you idiot?"

He gulped. Not a good start. Oh well…

"Coming to talk to you."

"And why did you have to fly up, knucklehead?"

"It seemed the most romantic way to do it. Course, you could tell me a better way, and then I'll do that."

She smiled slightly. Good. It wasn't even a mischievous or mocking smile. It was a smile that said, "You almost made me laugh."

"Well, now that you're here, what do you want to talk about?"

"Well, things like where, how, and what time I should meet you; what I should wear; how much money I should bring; _what_ I should bring, where we should go first… I know that the whole going with Snape thing was just a spot of mischief."

"Okay, it _was_ a spot of mischief. But that still doesn't mean I'm going with you."

"Right then, first things first. Will you go to Hogsmeade with me?"

"Oh, alright. But this doesn't mean I'll be going out with you permanently. This is just because I didn't get another offer. Okay?"

"Okay. Where do I meet you?"

"Common room, I suppose. Eight-thirty. You greet me as a friend, not as a girlfriend, got that? We're not going out."

"And the money?"

"Oh for heavens' sake! Just bring as much as you think you should. And get out of here now, I need my sleep."

"See you tomorrow then, Lily."

As he soared down, once more under his invisibility cloak, James noticed that the moon looked slightly bluer than usual.

Remus was gone when he got back. Well, he had only said he'd stay there all night if James had conjured up a bedroom, hadn't he? He was probably up in the dormitory, snoring away. James picked up his gear, and walked back to the dormitory.

Remus wasn't there, either.

_Maybe he's raiding the kitchens? But he'd have taken Padfoot and Wormtail if that was it. It can't be that he's transformed; the moon's a week past the full. What's happened?_

He was getting worried now. He'd better go look for him. But he'd need more than a stag to find him. He'd need someone with an amazing nose, and someone who could get through a few tight spots…

Sirius and Peter were definitely there. You'd think they had loudspeakers strapped to them by the sound they were making. He could easily shake them awake, but… maybe if he cast _Muffliato _on everyone else…

After three _Muffliatos_, the other people in the room wouldn't wake up if a wounded hippogriff roared in their ear. And, since snoring was what these two did best, they certainly deserved someone to show them how good they were at it.

He cast _Sonorus _on the two sleepers. They woke immediately. Two _Quietus_es later, the room was silent.

Sirius was the first to break the silence. "Why did you do that, you bastard?"

James grinned. That had been fun. But he had no time for fun now.

"Moony's gone missing. I've got no idea what happened to him. We've gotta go look."

"M-M-M-Moony's m-m-missing?"

"Your powers of hearing are amazing, Wormtail."

"H-How?"

"Or not. I don't know, that's what makes me worried. If he'd been raiding the kitchen, he'd have taken you two. Come on, let's go."

"Alright, let's go. But I haven't forgiven you for waking us up yet."

Fifteen minutes later, a bear-like black dog accompanied by a stag with a rat riding on its antlers galloped across the grounds.

They went towards the place where James had been. Sirius sniffed around, trying to find a scent. After about a minute, he froze, popped back to human for just long enough to say, "Got it." Then went back to dog. He ran off, nose to the ground, and James keeping pace beside him. Suddenly, Sirius stopped, and became human again. James followed suit.

"What's wrong, Padfoot? You look weird."

"Well, by the way the scent's going, he was going back to the castle. But then he stopped, and his scent changed. He smells like he's in his wolf form. Then he ran off to the forest."

"His wolf form? But it's not the full. What's going on?"

"I don't know, but it's not good. We'd better go after him. And James? Full alert. It smells like his wolf form, but it's stronger than it should be. Which means one of three things: we're right behind him, he stayed here for a couple of hours, or he's bigger than normal. Be ready to fight."

"I don't want to hurt him."

"If you don't, he may kill you," said Sirius, looking more serious than James had ever seen him.

**Chapter Three**

They'd been searching for seven hours before Sirius finally hit on a fresh scent. He bounded off, into a patch of deep, deep undergrowth.

There was a clearly defined path, which had obviously been made by a large animal. They broke into a run. Sirius now had his nose in the air. If he could smell Remus on the air, they were within a hundred meters.

Through the bushes, over a hill, down a valley, around a corner… and there he was.

An enormous wolf, flanks heaving, mouth frothing, skin stretched taut with the muscles. It was at least three times as big as Sirius' dog, and was obviously strong and smart enough to kill them all.

It snarled at them and advanced. They backed away. It advanced. They backed off. It lunged at James. James leaped straight into the air, high over the gigantic _thing_. But now the first move had been made. The fight was on, but they couldn't risk it. They tried to run away, but they couldn't outrun it. Their only hope was that the moon would die. Then he'd transform back, and they could take him to the hospital wing.

But although it was nearly dawn, the moon showed no signs of going down, and they were getting tired. They'd managed to keep from being torn open by turning and ducking so far, but not for much longer. A hundred meters off was a clump of thick trees with low branches. If they ran in there, they'd be able to catch their breath, while the monster wolf tried to find a way in.

James felt a surge of hope. He pushed himself a bit further, straining every muscle, thinking he might make it.

Then he felt warm breath on his neck.

The monster was right behind him.

If he'd thought he was sprinting before, he'd been wrong. _Now_ he was sprinting, going at least 65 kilometers an hour. He'd almost reached the clump… he was there! He'd made it! He was safe for a while! But then…

He heard an unearthly scream. The wolf had found something. He peered out.

Apparently the wolf had figured out that if it couldn't catch something with its teeth, its forelegs had a longer reach…

Sirius was lying on his side, with one of his legs torn open to the bone. It wouldn't kill him, but it would stop him using it. And he was gushing blood. The wolf was above him. Sirius was about to die. No hope. But maybe, just possibly…

Sirius looked at him. A mournful look. He seemed to be losing consciousness. Then he whined, and passed out.

That decided it. He shook his head until Wormtail fell out of his antlers. Then he lined himself up and charged. The wolf looked at him, an inch away from biting into Sirius' remaining limbs.

It must have been surprised.

It closed its mouth, faced James, opened it again and roared loud enough to slow James in his stride.

And that was when James lowered his head, and stabbed the wolf in the face with all fourteen points on his antlers.

There was another unearthly scream, and the wolf shook himself free, prancing about with the pain.

James galloped over to Sirius and pushed him. The wolf was angry, but Sirius was almost there.

One last shove… Sirius was safe. And the wolf had recovered. James sprang for the bush, and almost made it. A hole appeared in his flank as he flew through the air.

He landed hard and fell over. He and Sirius were both bleeding heavily. His own wound wasn't that serious, just painful. The wolf, now mad with pain and anger, was literally ripping branches off the trees. He'd be in within ten minutes. But at last - at long last - the sun was rising. And the moon was setting. The wolf was getting weaker. It was a race between how long it took for the wolf to get in and how long the moon took to set. It would be close. And if the wolf won, they were finished. They could run no more.

Ten minutes later, the wolf was one branch away from killing them. The moon was almost down, but it would take too long. Too long! They were dead for sure.

From where he was laying, James could see Peter in a tree.

Just sitting there, staring alternately at them and the wolf.

He appeared to come to a conclusion of some sort. He sprang from the tree, landing right next to James, while changing into his human form.

"Quick, James! Become human! I need you to help me!"

James had no idea what he was babbling about.

"You're too heavy for me to drag like this! Come on, James!"

Finally, James understood. He quickly transformed and pushed with his good leg while Peter pulled. They managed to move a bit, enough to give him about ten seconds more, at the rate Remus was going.

But the beast, seeing his meal escaping, became even angrier. He began tearing apart the foliage with renewed energy. And, even with both of them working at getting away as hard as they could, soon they would be caught. Sirius was far enough off to not be hurt, but he already was hurt badly. He couldn't help.

Another clock had been set and was ticking. Now it was a race between how fast they could go, how fast Remus could go, and when the moon went down. There was a sliver of moon above the horizon, a sliver of wood left, and not even a sliver of energy left in their tired limbs. One clock had stopped. The others would both stop in under half a minute. And then it really would be the end.

James shut his eyes and felt Peter shrink. His last thought was, _At least my friends are safe._

The wolf tore off the last branch and pounced.

James opened his eyes and wondered why he was alive. He'd felt the pain and weight as the wolf landed on him, razor-sharp claws out. He'd felt the shift in weight as it leaned forward, head lowering. He'd passed out from pain and loss of blood. And now, after being unconscious for God knew how long, he was still alive. Had Sirius woken up and knocked the wolf off him? Had Peter, small though he was, done it?

He looked up. He'd only been out a few minutes; the sun still hadn't quite risen.

There was a weight on his stomach. He looked down.

It was Remus. No longer an enormous wolf, but a smallish boy; he was unconscious, as he always was after a change.

He looked around. Peter was trying to waken an unconscious Sirius. He looked bad. He was still a dog, which was good, because the dog could stand to lose a lot more blood than a human could. James changed to a stag. He twisted so Remus was on his back and stood up. He scooped Sirius onto his back as well, and collapsed under the weight. He was still bleeding from the leg, and the dog was heavy. Peter pulled out his wand and was obviously going to try to make Sirius float. He managed the tricky charm, and James was able to stagger forwards. In this manner, with Peter running along, Sirius floating ahead - somewhat erratically from being held there by unpractised hands - Remus waking up on James' back, and James bleeding, they made it to the edge of the woods. Here, Peter put down Sirius and ran to Madam Pomfrey while James tried to wake Sirius so he could transform.

"_Enervate. Enervate. __**Enervate,**_" he muttered over and over. Finally, Sirius woke up, and he changed back just as Madam Pomfrey came bustling towards them.

"Oh, what have you boys been doing this time? Oh no…" she said, her voice softening after seeing Remus. "He changed to a wolf again last night, didn't he? And you went after him? You poor fools. But why did he change?" she muttered to herself. After a while, in which she stopped their bleeding, she suddenly became her own brisk self again.

"Right! I'd better get you boys up to the castle." She conjured up a few stretchers, and floated the boys onto them. Up at the hospital, she rubbed something into their wounds that stung, but made the wounds disappear. After that, she forced them all to drink a blood-replenishing potion. After fifteen minutes, James glanced at the clock.

"Madam Pomfrey?"

She poked her head in. "Yes, dear?"

"Is that clock right?"

"Yes, of course it is," she sniffed.

James bolted from his bed and ran all the way to the Gryffindor common room.

He was just in time for his date with Lily.


End file.
